There are previously known hydraulic rock drilling machines that are controlled with the aid of a distribution valve which is arranged in connection with the percussion device. The distribution valve aims to provide intermittent pressurizing of the driving chamber for the impact piston in order to achieve desired percussive function.
Distribution valves so far known function well but require precision machining in order to guarantee reliable valve function, in particular in respect of today's rock drilling machines with increased percussive frequencies. This influences the costs of the valve and thereby of the rock drilling machine as a whole negatively.
As an example of the background art can be mentioned U.S. Pat. No. 2,034,122 A1, which describes a rock drilling machine including a valve with a removable valve end wall.